The art of sailing essentially deals with the positioning of the main sail or the main sail boom in relationship to the apparent wind and the course or direction of the boat. The direction of the apparent wind (which is defined by two vectors: the actual wind speed and direction and the boat speed and boat direction or course) may be indicated by many known means being it by so-called tell-tails at the forestay or shrouds or by wind vanes, usually placed on top of the mast, and such devices may range from simple pieces of cloth or string to complicated and highly precise wind and wind speed indicators. Typical of such devices are represented by the following references of interest.
______________________________________ Patent Number Date Inventor ______________________________________ 419,608 January 14, 1890 Maret 2,363,087 November 21, 1944 Salisbury 3,371,529 March 5, 1968 Tillman 3,478,585 November 18, 1969 Scannell 3,641,815 February 15, 1972 Fassett 3,845,734 November 5, 1974 Demos ______________________________________
Maret discloses an anemoscope consisting of a wind or weather vane being placed on top of a spindle having at the other end a gear designed to activate a pointer which indicates the compass direction of the wind. This device, suggested to be used on, for instance, the gable of a house, would not be useful for the intended purpose of this invention.
Salisbury describes a wind course indicating means which provide the sailor information about wind direction with respect to the boat's course. This device does not teach the sailor where to position the main sail boom.
Tillman is concerned with a wind vane indicating the direction of the (apparent) wind, however, no means are provided for indicating where to locate the main sail boom in relation to the boat.
Scannell deals with a sailing accessory including a wind vane mounted on top of the mast, actual boom position actuating means, indicating means for apparent wind direction, actual and desirable boom directions, as well as means for transmitting wind direction information via a combination of selsyn generator, signal transmitting means and synchromotor plus suitable gearing arrangement; also servo-mechanism type connection between boom position activating means and indicating means therefor. This sophisticated if not complicated accessory is permanently attached to the respective location i.e. the wind vane on top of the mast, the indicating means below deck or in the cockpit, and the boom position activating means at the junction of boom and mast. Because of items such as selsyn generator, synchromotor, electrical connections therefor as well as indicating gear and servo-mechanism and the like, such a system is costly because it must be protected from moisture and especially salt water spray if used off coast.
Fassett teaches a wind indicating system allowing read-out of apparent wind angle in relation to boat direction either on 0-180 degree scale of a 20-50 degree port or starboard scale. Nothing is provided to indicate desirable main boom position.
Demos deals with an apparent wind indicator and indicating means for aligning the boom to a favored position on one particular course. This system lacks means for indicating desirable boom position regardless of boat course in relation to wind.
The wind direction devices also providing information of the desirable boom position are either too complicated, too heavy or too expensive to be useful on a boat employed for teaching the art of sailing to a novice or to provide indication means to the more experienced sailor, such means being readily installed, readily maintainable, simple in design and readily understandable.